Ali, a summer intern at the University of Hawaii, shares her experience from the cruise that will install the ALOHA Cabled Observatory.

Monday, June 6, 2011

When Lord Kelvin Was Napping

I woke up to find more water column. I was under the impression that at 0400 I would awake to watch the connectors being plugged in and the puzzle pieces being put together.Jason had descended the evening prior and would have had plenty of bottom time by then.Apparently, though, as I was sleeping a puzzle pieces – a piece of twine – got sucked into one of Jason’s thrusters and he had to be brought up, patched up, and redeployed. I arrived on the scene just in time to soak in a couple hours of the water column as he descended and a little bit of “Jason on bottom.”

The rest of the day was slow.The back deck is so lonely now that all the equipment is at the bottom of the ocean.They were all having an exclusive get together down there to which only those who can withstand 5000 decibars of pressure are invited. Jason was the guest of honor, Medea came as a member of the press, and the rest of us got to watch the celebrities live on Channel Jason. We watched cables being un-bungeed from the AMM and strung across the mud to the observatory. The same for the camera tripod and the TAAM mooring.

While we sat and observed Jason go to work, the conversation drifted to physics in the ocean.Roger pointed out to me the places in which Newtonian physics plays clear and important roles in the dynamics of the ocean and atmosphere. Though oceanography is fairly new to me, Newtonian mechanics make things clearer to me in all settings. You can see it in propagation of El Nino effects across the Pacific in the form of Kelvin waves. You can see it in white caps and waves forming at the ocean’s surface due to the wind’s drag– manifesting the Kelvin-Helmholtz instability – and how that affects the development of hurricanes. You can see it in the rotation of the earth resulting in the Coriolis Effect. I addition to learning about Roger’s work and how simple physics concepts fit into complicated questions like ‘how does the ocean affect the atmosphere?’ I learned that Lord Kelvin, as Roger put it, is ubiquitous. From the 0 K air-conditioned control van, to Kelvin waves to Kelvin-Helmhotz instability, Lord Kelvin pops up everywhere on this ship.

In the afternoon, when my personal physics lecture was over and Lord Kelvin was napping, I popped into the Jason van for my 1600 to 2000 Jason watch.When I took over the event logger, Jason was returning to my lounge chair to begin unraveling the second neon green cable and stringing it out to the observatory.Before we did so, we decided to scan the mooring up and down because opportunities to examine moorings while they’re in the water are few.At about 5 m up, the cameras zoomed in on the inductive modem to find that the cable intended to connect it to the rest of the observatory had come unplugged.Unfortunately this connector is not one that can be reconnected under water.This means that the data from the thermistor array will not be available in real time to Makaha. Luckily, though, the instruments are already programmed to collect data autonomously, which can be collected in a few years when the mooring is recovered.

After watch, with no recliner from which to observe the stars, I ‘re-racked’ in preparation for 0400 to arrive again.